Manufacture of paper making material



Patented Nov. 24,; 1931 j arse STATES.

Arum-forms,

'10 K WATANABB, OI KA GOYA, JEAN mama or urea No Drawing. Applicationfled llovcniber I, 1888, Serial 1T0. 404,210,,and in Japan January 23,1989;

This invention relates to im rovements in the manufacture of paper ma gin order to recover pulp by deinking of old printed paper.

. The characteristic feature of this invention is to make an emulsion ofcamphor oil, a

solvent of printing ink and dry printing ink, by the action of suitabledispersing medium such as soap solution, and to mix the resultantemulsion of oamph or oil with old printed aper treated'with alkali andthereby de-ink y the dissolution and dispersion of ink mat ter into thesaid dispersed solvent oil.

The object of this invention is to attain the 1 deinking of old printedpaper easily and completely so it can recover a useful paper mak- -1ngmaterial having the same grade to that of the old paper used by a simpleand economical process.

Heretofore old "printed paper has not been utilized as 'arawmaterial'for the recovery of high grade paper pulp on account of thedifiiculty of 'deinking. v But, by the improved method of this inventionthis .old printed paper may be satisfactorily used as a raw material forthe same purpose, and also a successful utilization of such waste matteras old printed paper can'be attained, of which there is an immensesupply. I

This invention is preferably carried out as follows: To make an emulsionof camphor oil a solution of soap made of any sort of The next treatmentis the tearing-0r breaking up of old printed paper. For this tearing apaper making kneaderis used, and for about 1,000 lbs. of the quantity ofold paper the aforesaid emulsion of camphor oil to-' gether with about 3lbs. of caustic soda solution and a proper quantity of. water are poureddown into the kneader through re-.

spective supply pipes provided at the charging'part of the kneader. Inkneading of this 7 .is then poured down into the paper making tcher orthe mixer and in this apparatus t is agitated by a constant rotation forabout tillirty minutes. During this agitation in t e fi xe on oldprinted paper is completely peptized into minute particles, and as aresult of,this the pigment most contained in printsuspended in thedispersed solvent oil. This dispersed mixture, therefore, containsminute particles 'ofpeptized ink matter so that if this (potcher or themixer dry printing ink ing ink such as lamp black is also completelymixture is scooped up and pressed in the hands there will be separated ablackish muddy liquor from the mixture and a white paper fibre willremain in the hands. From this experiment it is clearly known thatpigments and other constitutents of printing ink are completely peptizedinto very minute particles in. the dispersed solvent oil so as to becapable of free passing through filter paper of the qualitativeanalysis.

The aforesaid strong peptization of dry 1 printing ink (containingpigment, varnish etc.) fixed on old printed paper by the action ofdispersed solvent oil comprising a mixture explained as below.

Camphor oil, in general, is a good solvent of dry varnish in printingink, and if camphor oil is added to old printed paper in a form ofemulsion there can be attained the result of filling the paper withcamphor oil in a great volume. When varnish in ink is disof emulsion andcaustic soda solution, will be solved in the dispersed solvent oil itthen forms a colloidal varnish, and as it is a substance easilyemulsified by soap solution varnish once dissolved in camphor oil it nowbegins to separate from the solution in a form of colloid by the aid ofagitating orstirring action and at the same time the dissolving actionof remaining varnish into solvent oil is again proceeded. v

Moreovercam-phor oil has the property of dissolving rosin present in oldprinted paper, and therefore it greatly weakens. the chemical afiinitybetween varnish and rosin by its presence resulting in the separation ofvarnish and rosin.

The soap solution itself, at the same time causes a peptizing action ofvarnish and rosin in the kneaded paper.

Caustic soda, on the other hand, is utilized toneutralize acidityderived from acid materials in paper such as sulphuric acid in anddispersing the ink matter in the said dispersing medi T h Ira witnesswhereof I have hereunto set my NAOSHIGE OSAWA.

alum-cake, alum and sizing materials such as rosin, and thus it canprevent the emulslon from its coagulation by acid and keeping theemulsion in good stability. Moreover caustic soda solution acts toexcite the pe tization of varnish and rosinin paper, sot at by thisaction size of paper is destroyed and the'chemical afiinity between,water and fibre can be promoted, while the chemical aflinity betweenvarnish, fibre and rosin being remarkably weakened. A greater part ofblack muddy liquor, which is completely peptized during the agitation inthe potcher or the mixer, may be separated by using an apparatus such ascentrifugal separator. The remaining fibre of paper thus gained is thenpoured into the potcher or the mixer with water. Thereupon it isrepeatedly washed by the drum washer or it may be poured down into atank having a mat stretched over its bottom and provided with agitatorsand in this tank the muddy liquor now becomes filtered and separated.

In actual practice of this washing process there rarel appear minuteblack spots on the washed pu p mixture-even when its quantity is verysmall. But these spots will completely vanish by washing and adding asmall quantity of alkali, as the said phenomena of black spots appearingis chiefly due to lack of the alkalinity of the kneeded paper mixture.Moreover this vanishing efiect 1s better attained when a small quantityof soap is added with alkali- The resultant product after the washing iscompletely deinked and the fibre has the same quality as that of thefibre consisting of old printed paper, can be obtained.

' The produced material thus gained is then printing ink bythe action ofsoap solution as dispersing medium, then mixing the resultant emulsionwith old printed paper. 'pneviay treated with an alkaliand finallydetheold printed paper by dissolving

